This is what it's like when you come to rely too heavily on PowerPoint. Can you still give your presentation if your technology fails? If not, you are too dependent on PowerPoint!
I'm seriously concerned about a whole generation of new presenters who have never stood in front of an audience alone without their PowerPoint partner. I asked someone, who's new to speaking, how long her typical presentations are and she replied, "Eight slides." What does that even mean?
Even a three-minute quickie presentation is accompanied by three slides. It's ridiculous. Yet there is a whole corporate culture that insists and demands that a presentation IS PowerPoint.
If your only presentation experience is speaking with a slide show behind you, I highly recommend finding ways to practice speaking without it.
Learn how to be with the audience, just yourself, your content, and your connection. Learn how to educate and inform an audience without slides. Learn how to paint mental pictures for them. Learn how to use your voice, your body and your face to emotionally engage them. Bring props and handouts. Write on a flip chart.
If your only experience is presenting with PowerPoint - especially the bullet- and text-laden kind - you are not really learning how to present. It's like walking onto the stage holding your security blanket or your scruffy little teddy bear every time you speak.
Take the opportunity, when you can, to let go of your partner. Get some practice presenting on your own. Learn how it feels not to have your "blankie." Learn how it feels to be with the audience and connect with them. It might be scary, but you will get better.
Then add PowerPoint back in if you must, but remember, you are the presentation, not your slides.